The Posted Order with map of the closure area can be found here. folsom lake trails map. D r. There is no trail access or alternate route within Folsom Lake State Recreation Area. P a rk w a y. Folsom Lake Crossing. If you took any photos please post them in the comments. State Recreation Area. . S o p h ia. East Natoma St. Folsom Lake. Main Body. Green Valley Rd. F ra n c is c o. Trail Map. Success at our Poker Ride! Thank you to everyone who attended.